Problem: Simplify the following expression: $n = \dfrac{8}{3r - 8} \div \dfrac{6}{9r}$
Answer: Dividing by an expression is the same as multiplying by its inverse. $n = \dfrac{8}{3r - 8} \times \dfrac{9r}{6}$ When multiplying fractions, we multiply the numerators and the denominators. $n = \dfrac{ 8 \times 9r } { (3r - 8) \times 6}$ $n = \dfrac{72r}{18r - 48}$ Simplify: $n = \dfrac{12r}{3r - 8}$